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Here is a photo of the first layup of a carbon fiber laminated bridge 2..oo9 carbon fiber weave laminates sandwiched between 3pcs of wood, 2.3.4 mm thick, 2 pieces of mulberry 1 walnut and for a total of abt 10mm The photo shows 1 side planed and the rear side as it first looked after the glue up using system 3 epoxy.It is vy light and extremely stiff.

Looks good. Keep us in the loop.

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"Act your age, not your shoe size" - Prince

Very cool, Ernie. Thanks for sharing the photos.

What is the goal for a carbon fiber laminated bridge? Is it to stiffen the bridge so it can be made lighter, or are there potential tonal benefits to having the carbon fiber in the bridge, unrelated to the weight savings?

Thanks chris an charlie,I will post pics of the completed bridge when finished.Basically the idea was taken from the new gore/gilet book on a contemporary upgrade to the traditional EIR or BRW classcical gtr bridge.the bridge is smaller in length 160 vs trad 175or more mm in L and abt 27mm W vs 29-31.mm. I/m no expert on this , as this a trial bridge , but the basic idea is to create a smaller footprint on the top which will effectively allow the top to vibrate freely .The wings are brought down to abt 2 mm at the ends vs the wider 4-5mm wings on a more traditional bridge.Also the weight will be in the 12-15 gm range vs the 20-25 range for an EIR bridge , these bridges can also be made with either 6 or 12 holes.By adding the carbon fiber laminates to the bridge it signifigantly increases the stiffness and decreases the weight.For all the scientific data and terminology,I would refer you to either trevor gore or one of the other aussie luthiers who could do a much better job of explaining the technical/scientific analysis / results of using this contemporary bridge regards ernie

The carbon layer is denser than the wood, so the only way it will reduce weight is if you make it smaller.

Is there a reason to make bridges stiffer ? they are already the stiffest brace on the guitar. Stiffer just means an even larger impedance mismatch between the bridge and the top.

Also remember, if you make the bridge lighter, you also make the resonant frequency of the top go higher so you will have to account for that in your overall bracing scheme.

-jd

Ernie - thanks for the explanation...makes sense. I look forward to seeing pics of the finished bridge.

John you are correct , with the addition of the carbon laminates, bridge will be smaller in length and width, and overall weight. I have not gotten to the impedance mismatch yet, but when I actually complete one of these new hi tech gtrs, it will be awhile yet.I am still trying to absorb the mtns of info in the gore/gilet book and put those ideas to practical use 1 new idea at a time including thicknessing of the tops/backs/sides and braces.

Good on you Ernie,....I am trying to assimilate and put into practice some of the things that Trevor and Gerard have put in their great tome. So far I have done live backs and now a falcate top but on a 14 fretter with a bit of jiggling it can be done. It is playing now and it is noticeably louder and very sweet as I have the resonances off scale tones and placed where they are suggested to be. I plan to do a nut and saddle compensation on the next one too. My building in the (nearly) year since I have had these books has come along in leaps and bounds. Also I was privileged to do a 3 day course with TG in January.... It was amazing and I am so grateful that they have made this information available.

John

Thanks for sharing john.Would love to hear from others trying carbon fiber bridges etc.

I used a Padauk and CF bridge on my last classical. The CF means you can use much lighter examples of your chosen wood and the CF maintains the stiffness. So its not just the size. I used two layers, the bottom layer is between the 18 holes for the strings. By passing the strings over the cf the holes are reinforced and you don't need to use bone. The top layer is put as close to the top of the bridge as possible (CL or SS). And I used a enclosed saddle slot so the cf layer at the top provides great reinforcement for the saddle. And then I can use a lower bridge and taller saddle to further shave weight. So there are many benefits beyond the obvious.
As to bridge length, Trevor mentions some research that showed that bridges work best if not longer than half the width of the lower bout which many classicals are. This is why the bridge is shorter. The wings simply provide glue area and so can be very thin.

I was able to use off-cuts from the back to make the bridge layers on my last MJ. Flamed blackwood, looked great and matched the B&S.

Cheers
Dom

thanks for the tip Dom. have not milled anything on bridge yet cheers ernie